Clarify javadoc for creation time

Author: cezarfx

driver/src/main/java/oracle/nosql/driver/ops/DeleteResult.java

@@ -63,7 +63,8 @@ public MapValue getExistingValue() {
      * {@link DeleteRequest#setReturnRow} are met.
      *
      * Note: If the row was written by a version of the system older than 25.3
-     * the creation time will not be available at all and will be zero.
+     * the creation time will be equal to the modification time, if it was
+     * written by a system older than 19.5 it will be zero.
      *
      * @return the creation time in milliseconds since Jan 1, 1970 GMT
      *

driver/src/main/java/oracle/nosql/driver/ops/GetResult.java

@@ -66,7 +66,7 @@ public Version getVersion() {
      * row does not expire. This value is valid only if the operation
      * successfully returned a row ({@link #getValue} returns non-null).
      *
-     * @return the expiration time in milliseconds since January 1, 1970 GMT,
+     * @return the expiration time in milliseconds since January 1, 1970, GMT,
      * or zero if the row never expires or the row does not exist
      */
     public long getExpirationTime() {
@@ -79,9 +79,10 @@ public long getExpirationTime() {
      * successfully returned a row ({@link #getValue} returns non-null).
      *
      * Note: If the row was written by a version of the system older than 25.3
-     * the creation time will not be available at all and will be zero.
+     * the creation time will be equal to the modification time, if it was
+     * written by a system older than 19.5 it will be zero.
      *
-     * @return the creation time in milliseconds since January 1, 1970 GMT,
+     * @return the creation time in milliseconds since January 1, 1970, GMT,
      * or zero if the row does not exist
      *
      * @since 5.4.18
@@ -100,7 +101,7 @@ public long getCreationTime() {
      * This value is valid only if the operation
      * successfully returned a row ({@link #getValue} returns non-null).
      *
-     * @return the modification time in milliseconds since January 1, 1970 GMT,
+     * @return the modification time in milliseconds since January 1, 1970, GMT,
      * or zero if the row does not exist
      *
      * @since 5.3.0

driver/src/main/java/oracle/nosql/driver/ops/PutResult.java

@@ -75,8 +75,10 @@ public MapValue getExistingValue() {
      * Returns the existing creation time if available. This value will
      * only be available if the conditions specified in
      * {@link PutRequest#setReturnRow} are met.
+     *
      * Note: If the row was written by a version of the system older than 25.3
-     * the creation time will not be available at all and will be zero.
+     * the creation time will be equal to the modification time, if it was
+     * written by a system older than 19.5 it will be zero.
      *
      * @return the creation time in milliseconds since Jan 1, 1970 GMT
      *

driver/src/main/java/oracle/nosql/driver/ops/WriteMultipleResult.java

@@ -219,6 +219,10 @@ public MapValue getExistingValue() {
         /**
          * Returns the creation time associated with the key if
          * available.
+         * Note: If the row was written by a version of the system older than
+         * 25.3 the creation time will be equal to the modification time, if it
+         * was written by a system older than 19.5 it will be zero.
+         *
          * @return the creation time if set, in milliseconds sine Jan 1, 1970
          * GMT
          *